接种不同乳酸菌对干玉米秸秆与白菜废弃物混贮品质的影响

Effects of inoculating different lactic acid bacteria on the mixed storage quality of dry maize straw and cabbage waste

动态研究植物乳杆菌（Lactobacillus plantarum,LP）和布氏乳杆菌（Lactoacillus buchneri,LB）对干玉米秸秆与白菜废弃物连续混贮170 d期间品质变化的影响,利用Mi Seq高通量测序平台考察细菌多样性.无添加剂设为对照组（ME组）,定期分析感官品质、有机化学组分、发酵品质和细菌多样性.结果表明,与ME组相比,30 d时LB和LP组干物质（DM）含量均显著（P〈0.05）下降,之后分别于60 d和90 d显著（P〈0.05）增加,且LB组始终高于LP组.贮存170 d期间LP和LB组中可溶性碳水化合物（WSC）含量显著（P〈0.05）高于ME组,且LB组始终高于LP组（除130 d）.30-90 d期间LP和LB组pH显著（P〈0.05）低于ME组,且LP组始终低于LB组,LP组乳酸（LA）含量显著（P〈0.05）增加,氨态氮/总氮（AN/TN）显著（P〈0.05）降低.130-170 d期间LP和LB组中乳酸/乙酸（LA/AA）和乳酸/总有机酸（LA/TOA）均明显低于ME组,乳酸发酵程度变弱.3个处理组中厚壁菌（Firmicutes）和变形菌（Proteobacteria）为门水平优势类群;乳杆菌（Lactobacillus）始终为属水平优势菌;2种乳酸菌剂均能使肠杆菌（Enterobacter）、假单胞菌（Pseudomonas）和黄杆菌（Flavobacterium）等腐败菌丰度显著（P〈0.05）降低,130 d时Enterobacter消失.总之,L.plantarum有助于改善混贮中前期（90 d）发酵品质,能有效保存纤维素、半纤维素和综纤维素等能源组分,L.buchneri有利于170 d贮存期间的DM和WSC保存;建议实际生产中根据贮存周期长短来选择适宜的乳酸菌,以便获得最佳贮存品质.

The effects of two microbial inoculants, Lactobacillus plantarum（LP） and Lactobacillus buchneri（LB） on the mixed storage quality of dry maize straw and cabbage waste for 170 days were studied dynamically, and the dynamic rule of microbial community diversity were also investigated by Illumina Mi Seq high-throughput sequencing. The control group（ME group） without additives was tested, and the sensory quality, organic chemical composition, fermentation quality, and microbial community diversity were analyzed regularly. The contents of dry matter（DM） in case of LP and LB decreased significantly（P〈0.05） after 30 d, but the content of DM in case of LP and LB were both significantly（P〈0.05） higher than that of the ME group after 60 d and 90 d, respectively. The content of DM was always higher in case of LB than in case of LP. The water soluble carbohydrate（WSC） content in case of LP and LB were significantly（P〈0.05） higher than that of the ME group after 170 days, and the WSC content in case of LB were higher than that in case of LP（except after 130 d）. The pH values in case of LP and LB were significantly（P〈0.05） lower than that of the ME group between 30 d and 90 d, and the pH in case of LP was always lower than that of LB. The contents of lactic acid（LA） in case of LP increased significantly（P〈0.05）, and the ratio of ammonia nitrogen to total nitrogen（AN/TN） decreased significantly（P〈0.05） compared to the ME group. The ratio of lacticacid to acetic acid（LA/AA） and the ratio of lactic acid to total organic acid（LA/TOA） were significantly（P〈0.05） lower than those in the ME group, and the intensity of lactic acid fermentation was weakened during 130–170 d. The dominant bacterial communities in the three groups were Firmicutes and Proteobacteria at the phylum level, while Lactobacillus was dominant in genus level. The abundance of spoilage bacteria such as Enterobacter, Pseudomonas, and Flavobacterium decreased significantly（P〈0.05） after inoculation of LP and LB, and Enterobacter disappeared after storage for 130 d. In conclusion, the fermentation quality was improved by the addition of LP after 90 d, and the energy components of cellulose, hemicellulose, and holocellulose were well preserved. The addition of LB facilitates the preservation of DM and WSCs for 170 d. It is suggested that suitable lactic acid bacteria should be selected according to the storage period in order to obtain the best storage quality.